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Scene perception in posterior cortical atrophy: categorization, description and fixation patterns

Partial or complete Balint's syndrome is a core feature of the clinico-radiological syndrome of posterior cortical atrophy (PCA), in which individuals experience a progressive deterioration of cortical vision. Although multi-object arrays are frequently used to detect simultanagnosia in the cli...

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Autores principales: Shakespeare, Timothy J., Yong, Keir X. X., Frost, Chris, Kim, Lois G., Warrington, Elizabeth K., Crutch, Sebastian J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3788344/
https://www.ncbi.nlm.nih.gov/pubmed/24106469
http://dx.doi.org/10.3389/fnhum.2013.00621
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author Shakespeare, Timothy J.
Yong, Keir X. X.
Frost, Chris
Kim, Lois G.
Warrington, Elizabeth K.
Crutch, Sebastian J.
author_facet Shakespeare, Timothy J.
Yong, Keir X. X.
Frost, Chris
Kim, Lois G.
Warrington, Elizabeth K.
Crutch, Sebastian J.
author_sort Shakespeare, Timothy J.
collection PubMed
description Partial or complete Balint's syndrome is a core feature of the clinico-radiological syndrome of posterior cortical atrophy (PCA), in which individuals experience a progressive deterioration of cortical vision. Although multi-object arrays are frequently used to detect simultanagnosia in the clinical assessment and diagnosis of PCA, to date there have been no group studies of scene perception in patients with the syndrome. The current study involved three linked experiments conducted in PCA patients and healthy controls. Experiment 1 evaluated the accuracy and latency of complex scene perception relative to individual faces and objects (color and grayscale) using a categorization paradigm. PCA patients were both less accurate (faces < scenes < objects) and slower (scenes < objects < faces) than controls on all categories, with performance strongly associated with their level of basic visual processing impairment; patients also showed a small advantage for color over grayscale stimuli. Experiment 2 involved free description of real world scenes. PCA patients generated fewer features and more misperceptions than controls, though perceptual errors were always consistent with the patient's global understanding of the scene (whether correct or not). Experiment 3 used eye tracking measures to compare patient and control eye movements over initial and subsequent fixations of scenes. Patients' fixation patterns were significantly different to those of young and age-matched controls, with comparable group differences for both initial and subsequent fixations. Overall, these findings describe the variability in everyday scene perception exhibited by individuals with PCA, and indicate the importance of exposure duration in the perception of complex scenes.
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spelling pubmed-37883442013-10-08 Scene perception in posterior cortical atrophy: categorization, description and fixation patterns Shakespeare, Timothy J. Yong, Keir X. X. Frost, Chris Kim, Lois G. Warrington, Elizabeth K. Crutch, Sebastian J. Front Hum Neurosci Neuroscience Partial or complete Balint's syndrome is a core feature of the clinico-radiological syndrome of posterior cortical atrophy (PCA), in which individuals experience a progressive deterioration of cortical vision. Although multi-object arrays are frequently used to detect simultanagnosia in the clinical assessment and diagnosis of PCA, to date there have been no group studies of scene perception in patients with the syndrome. The current study involved three linked experiments conducted in PCA patients and healthy controls. Experiment 1 evaluated the accuracy and latency of complex scene perception relative to individual faces and objects (color and grayscale) using a categorization paradigm. PCA patients were both less accurate (faces < scenes < objects) and slower (scenes < objects < faces) than controls on all categories, with performance strongly associated with their level of basic visual processing impairment; patients also showed a small advantage for color over grayscale stimuli. Experiment 2 involved free description of real world scenes. PCA patients generated fewer features and more misperceptions than controls, though perceptual errors were always consistent with the patient's global understanding of the scene (whether correct or not). Experiment 3 used eye tracking measures to compare patient and control eye movements over initial and subsequent fixations of scenes. Patients' fixation patterns were significantly different to those of young and age-matched controls, with comparable group differences for both initial and subsequent fixations. Overall, these findings describe the variability in everyday scene perception exhibited by individuals with PCA, and indicate the importance of exposure duration in the perception of complex scenes. Frontiers Media S.A. 2013-10-02 /pmc/articles/PMC3788344/ /pubmed/24106469 http://dx.doi.org/10.3389/fnhum.2013.00621 Text en Copyright © 2013 Shakespeare, Yong, Frost, Kim, Warrington and Crutch. http://creativecommons.org/licenses/by/3.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Neuroscience
Shakespeare, Timothy J.
Yong, Keir X. X.
Frost, Chris
Kim, Lois G.
Warrington, Elizabeth K.
Crutch, Sebastian J.
Scene perception in posterior cortical atrophy: categorization, description and fixation patterns
title Scene perception in posterior cortical atrophy: categorization, description and fixation patterns
title_full Scene perception in posterior cortical atrophy: categorization, description and fixation patterns
title_fullStr Scene perception in posterior cortical atrophy: categorization, description and fixation patterns
title_full_unstemmed Scene perception in posterior cortical atrophy: categorization, description and fixation patterns
title_short Scene perception in posterior cortical atrophy: categorization, description and fixation patterns
title_sort scene perception in posterior cortical atrophy: categorization, description and fixation patterns
topic Neuroscience
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3788344/
https://www.ncbi.nlm.nih.gov/pubmed/24106469
http://dx.doi.org/10.3389/fnhum.2013.00621
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